code: def evaluation_fn(step, width, height):
      time.sleep(0.1)
      return (0.1 + width * step / 100) ** (-1) + height * 0.1
  
file_path: ray/python/ray/tune/examples/logging_example.py
imports: import argparse
  import time
  from ray import train, tune
  from ray.tune.logger import LoggerCallback
label_desc: Use image node_id 2 for calling a global function with example usage: evaluation_fn(step, width, height) and returns: unknown